On Thu, Oct 21, 2010 at 9:03 AM, Janez Zemva <[email protected]> wrote:
> My approach to tackle this problem was to compile the entire ffmpeg.c > into my app and use it just like a command line utility within from my > application. The problem with this approach was, that while the use of > the ffmpeg utility is the same across all platforms. The results of > conversion certainly aren't (for all tested output formats). > Generally, the output of the same version ffmpeg, running on the > iphone, was worse, than the ouput of ffmpeg, running on the desktop > PC, using the same conversion parameters. > > 2010/10/20 ifrim alexandru <[email protected]>: > > --- On Wed, 10/20/10, John Gladman <[email protected]> wrote: > > > >> From: John Gladman <[email protected]> > >> Subject: Re: [libav-user] Using FFmpeg in iPhone Project > >> To: "Libav* user questions and discussions" <[email protected]> > >> Date: Wednesday, October 20, 2010, 1:56 PM > >> Hi > >> > >> What would it cost to provide a sample iPhone APP. I want > >> to convert a video file from AVI to an MP4 file that will > >> play on the iPhone. > >> > >> My problem is that I am currently creating an AVI file > >> within my APP but AVI files won't play on the iPhone. Thats > >> why I want to be able to convert it to > >> a format that will play on the iPhone. > >> > >> John G > >> > >> On 20 Oct 2010, at 18:50, Igor R wrote: > >> > >> >> Does anyone have a simple sample iPhone project > >> that allows video to be converted from one format to > >> another > >> > > >> > I don't have such a sample project, but I do develop > >> projects for > >> > iPhone with ffmpeg libs (libavcodec etc), and it > >> doesn't differ from > >> > using ffmpeg on Windows. Actually, we compile on > >> multiple platforms > >> > the same portable c++ code, which uses ffmpeg. > >> > _______________________________________________ > >> > libav-user mailing list > >> > [email protected] > >> > https://lists.mplayerhq.hu/mailman/listinfo/libav-user > >> > >> _______________________________________________ > >> libav-user mailing list > >> [email protected] > >> https://lists.mplayerhq.hu/mailman/listinfo/libav-user > >> > > > > As Igor mentioned the code is the same as on other platforms, but here's > a sample (from what I remember it was working correctly, I haven't > used/tested it much though). To convert to mpeg4 you'll need to make some > changes (it requires some strict parameters from what I recall). > There's a lot of assembly code in FFmpeg, which is CPU-specific. I assume this could cause one platform to behave differently than another, and even within the same platform depending on the compiler. For example, from what I understand the Intel C compiler does a better job at optimizing x86 code than GCC (while sacrificing strict compliance, perhaps), but all of this is moot if it's already written in assembly. Someone please correct me if I'm wrong. Thanks. _______________________________________________ libav-user mailing list [email protected] https://lists.mplayerhq.hu/mailman/listinfo/libav-user
